The wind-driven Thomas Fire exploded to 31,000 acres with zero percent containment overnight Monday into early Tuesday morning, destroying 150 structures, according to Ventura County fire officials.
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The blaze broke out Monday and grew wildly to more than 48 square miles in the hours that followed, consuming vegetation that hasn't burned in decades, Ventura County Fire Sgt. Eric Buschow said.
There was no immediate word whether the structures destroyed were mostly homes or businesses. Vista del Mar Hospital, a behavioral health care facility in Ventura, was razed to the ground by the blaze, ABC7 reporter Sid Garcia confirmed from the scene. All patients and staff were evacuated Monday night.
Multiple homes in the area of Scenic Way Drive in Ventura could be seen burning from the air. In downtown Ventura, the Hawaiian Village apartment complex was engulfed in flames. Other homes on High Point Drive above Foothill Road in Ventura were burning as embers blown by whipping winds filled the air.
More than 27,000 people have been evacuated and one firefighter was injured. There was no word on the extent of the injuries. Authorities said at least one person was killed in a car crash connected to the fire. A source told Eyewitness News the person appeared to be fleeing from the blaze.
The fire continued to burn west "out of control," according to fire officials, due to strong east winds that grounded aerial flight crews overnight. The winds were pushing it toward Santa Paula, a city of some 30,000 people about 60 miles northwest of Los Angeles. Many of the evacuated homes were in that city.
However, evacuation orders were expanded to houses in Ventura, which is 12 miles southwest and has 106,000 residents.
"The fire growth is just absolutely exponential," Ventura County Fire Chief Mark Lorenzen said. "All that firefighters can do when we have winds like this is get out ahead, evacuate people, and protect structures."
Structure protection operations were in place, but fire officials said crews were having trouble accessing some areas due to the intensity of the flames. Fire officials also warned of worsening conditions amid strengthening winds Tuesday.
Thomas Aquinas College, a school with about 350 students, has also been evacuated, with students going to their own homes or to those of faculty and staff, the college said in a statement.
One person was killed in an auto accident associated with the fire, officials said. They gave no further details.
Winds exceeding 40 mph and gusts over 60 mph have been reported in the area and are expected to continue, the National Weather Service said. Fire officials said the winds increased overnight.
Firefighters from neighboring Los Angeles and Santa Barbara counties were pouring in to help.
Nearly 180,000 customers in the Ventura county area were without power, Southern California Edison said on Twitter.
All schools in the Ventura Unified School District are closed on Tuesday.
(The Associated Press contributed to this report)